A circle which touches the three sides of a traingle internally is called the incircle.The center of the circle is called the incentre and the raidus is called the inradius.

If r is the inradius, then

The circle which passes through the vertices of a triangle is called the circumcircle of a triangle or circumscribing circle. The centre of this circle is the circumcentre and the radius of the circumcircle is the circumradius.

If R is the circumradius, then

If Δ is the area of the triangle,

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Re: Trigonometry Formulas

Re: Trigonometry Formulas

ganesh wrote:

Formulas which express the sum or difference in product

Hey ganesh i just joined this forum. i am an engineer. Am preparing for CAT exam.am sure u knw abt CAT. (its this november) . So i was looking for some really interesting geometry and number system stufflike some patterns or some formulaesetc

Re: Trigonometry Formulas

Hi kavish2000,I am sorry for the delay in replying,Yes, I know about CAT, the general questioning pattern etc.But what exactly do you want to know in Geometry and Number stuff?Any prearatory CAT book gives the basics. And CAT doesn't require the highest level of Geometry skills or Number theory skills. Beig familiar with UG level mathematics and to some extent PG level would do.

The wikipedia always has much interesting stuff in geometric and number system, provided you know what exactly are the search words you use, and depending on your luck when choosing the relevance percentage.

There are some other interesting forums, sites on the net. If I were you, I would exhaust all search engines, and just hope I am lucky!

Not many engineers pursue the CAT, and most of them who do are likely to be successful. My cousin is one, just about my age, and he's now with an MNC at middle/top management.

My good wishes to you for the CAT, its November already.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.